| 摘要 |
<p>A wireless optical short-range communication system adapted for use as an intercom system. The system can be used in fast food restaurants and similar commercial institutions. The communication system (Fig. 4) includes a base station (12) to interconnect via optical communication a group of substantially similar physically spaced-apart, remote units (14, 16). Each one of the remote units includes an optical emitter (33, 37) to transmit an optical message-carrying beam to the base station, and an optical receptor (35, 39) to receive an optical message-carrying beam from the base station. The base station includes a receptor (30) for receiving the optical beam transmitted by the optical emitters of all of the remote units, and an optical emitter (28) to relay the received optical beam to the optical receptors of all the remote units. The base station includes a clock arrangement for synchronizing the operation of the system in a time division multiplexing carrier arrangement, by providing individual discrete time slots for the transmission of the signals from the remote units to the base unit, and for the transmission of the signals from the base unit to the remote units.</p> |
